The present invention relates to mixtures of ethyl substituted tricyclic isochromans defined according to the structure: ##STR2## wherein R.sub.1, R.sub.2 and R.sub.3 represent methyl or hydrogen with the proviso that when one of R.sub.1, R.sub.2 and R.sub.3 is methyl, the other of R.sub.1, R.sub.2 and R.sub.3 represents hydrogen; and organoleptic uses thereof as well as intermediates for producing said compounds defined according to the structure: ##STR3## wherein R.sub.1, R.sub.2 and R.sub.3 are defined, supra; and wherein R.sub.4 represents C.sub.1 -C.sub.6 lower alkyl and according to the structure: ##STR4## wherein R.sub.1, R.sub.2 and R.sub.3 are defined, supra.
There has been considerable work performed relating to substances which can be used to impart (or alter, modify or enhance) flavors and fragrances to (or in) various consumable materials. These substances are used to diminish the use of natural materials, some of which may be in short supply and to provide more uniform properties in the finished product. Sweet and musky aroma characteristics and sweet and musky flavor characteristics are particularly desirable for many uses in foodstuff flavors, particularly pear, apricot and peach flavors. Musky aromas are desirable in several types of perfume compositions and for use in perfumed articles.
The production of isochromans has been shown in the prior art and certain novel isochromans have recently been disclosed with an outstanding musk fragrance. Such isochromans especially adapted for perfumery by virtue of their fragrance properties have been disclosed in Heeringa and Beets, U.S. Pat. No. 3,360,530 issued on Dec. 26, 1967.
A number of routes have been shown to be available for the production of isochromans, such as those set forth in U.S. Pat. No. 3,360,530 and one of the most straight forward of these routes in treatment of a Friedel Crafts reactant with an alkylene oxide under Friedel Crafts conditions to form an aryl alkanol. The aryl alkanol is then isolated and thereafter reacted with formaldehyde to cyclialkylate the alcohol.
In addition, several other references set forth processes for the production of isochromans such as U.S. Pat. No. 3,532,719 and U.S. Pat. No. 3,910,964 as well as U.S. Pat. No. 3,978,090.
The aforementioned references set forth production of compounds having the structure: ##STR5## using as a precursor pentamethyl indane having the structure: ##STR6##
U.S. Pat. No. 4,265,818 sets forth production of compounds defined according to the structures: ##STR7## using as a precursor the tetraalkyl indane having the structure: ##STR8##
More specifically, U.S. Pat. No. 4,265,818 discloses a product consisting essentially of compounds having the structures: ##STR9## produced according to the process comprising the steps of (i) reacting isoamylene with alpha methyl styrene according to the reaction: ##STR10## in the presence of a heterogeneous solid catalyst selected from the group consisting of acid clays and acid ion exchange resins, the mole ratio of isoamylene to alpha methyl styrene being between 1:1 and 2:1; the ratio of catalyst to reactants being from 0.1% up to 8% of the total weight of alpha methyl styrene and isoamylene; the reaction temperature being between 75.degree. C. and 250.degree. C.; the reaction pressure being between 50 psig and 300 psig; (ii) reacting the resulting product with propylene oxide in the presence of a catalyst to produce a mixture consisting essentially of indane alkanols according to the reaction: ##STR11## and (iii) reacting the mixture consisting essentially of indane alkanols with a formaldehyde or a formaldehyde source according to the reaction: ##STR12##
The said U.S. Pat. No. 4,265,818 also indicates the use of the compounds and mixtures so produced for augmenting or enhancing food flavors and fragrances. Specifically, the compounds of U.S. Pat. No. 4,265,818 indicate the usefulness of the compounds and mixtures produced for augmenting or enhancing musky aromas and pear, apricot and peach flavors.
U.S. Pat. No. 4,250,200 issued on Feb. 10, 1981 discloses and claims a process for augmenting or enhancing the pear aroma or taste of the pear flavor foodstuff comprising the step of adding to said foodstuff a flavor aroma augmenting or enhancing quantity of a mixture of compounds having the structures: ##STR13##
U.S. Pat. No. 3,978,090 issued on Aug. 31, 1976 discloses and claims processes for producing compounds defined according to the structure: ##STR14## as well as compounds defined according to the generic structure: ##STR15## wherein R.sub.1 ' and R.sub.2 ' are each (i) separately selected from the group consisting of hydrogen, lower alkoxyl or lower alkyl, and (ii) taken together, as selected from the group consisting of benzo, cyclopentano, cyclohexano, naphtho, monoalkyl cyclopentano, polyalkyl cyclopentano, monoalkyl cyclohexano and polyalkyl cyclohexano, and R.sub.3 ' and R.sub.4 ' are the same or different and are selected from the group consisting of hydrogen and lower alkyl. The compounds defined according to the structure: ##STR16## are indicated to be produced according to the reaction: ##STR17## wherein R.sub.5 ' and R.sub.6 ' are each 2-propyl. Indicated as a starting material at column 5, line 22 of U.S. Pat. No. 3,978,090 is the compound defined according to the structure: ##STR18##
Ethyl substituted tricyclic isochroman compounds having musk aromas are also disclosed in Beets, "PARFUMERIE/LES MUSCS/Scteur et Odeur", La France et ses Parfums 10 (1953), 1957 wherein the compound having the structure: ##STR19## is disclosed as having a musk aroma.
Nothing in the prior art however, discloses the existence of the ethyl substituted tricyclic isochromans defined according to the structures: ##STR20## or intermediates for preparing same having the structures: ##STR21## or: and nothing in the prior art discloses the unexpected, unobvious and advantageous organoleptic properties of the compounds defined according to the structures: ##STR22## or mixtures of same.